From: anjiandi@codeaurora.org
To: Mark Rutland <mark.rutland@arm.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
linux-kernel@vger.kernel.org,
Shanker Donthineni <shankerd@codeaurora.org>,
ard.biesheuvel@linaro.org, harba@codeaurora.org
Subject: Re: ARM64 TPM start method patches
Date: Thu, 13 Apr 2017 23:58:24 -0500 [thread overview]
Message-ID: <9890ce2f139b4204d17c6a398681083f@codeaurora.org> (raw)
In-Reply-To: <20170411113652.GB32267@leverpostej>
Adding Harb Abdulhamid for SMC details
On 2017-04-11 06:36, Mark Rutland wrote:
> Hi,
>
> I just stumbled upon the following commits in next-20170411:
>
> cf8252ca7ca76fa4 ("ACPICA: Update TPM2 ACPI table")
> 08eff49d63ca2bf4 ("tpm/tpm_crb: Enable TPM CRB interface for ARM64")
>
> ... which leave me a little concerned, for two reasons.
>
> Firstly, the spec these are based on (TCG ACPI Specification Family
> “1.2” and “2.0” Version 1.2, Revision 8), is a draft, open for public
> review until April 28th 2017 [1], and still subject to change, as noted
> in the title page of the document [2]:
>
> This document is an intermediate draft for comment only and is
> subject to change without notice. Readers should not design
> products
> based on this document.
>
> ... so I hope the plan is not to merge these until the final spec is
> published.
>
> Secondly, the spec is very vague as to the workings of the SMC call,
> and
> does not define:
>
> * That the SMC call follows the SMC Calling Convention [3]
> * The parameters to the SMC call
> * The return value(s) of the SMC call
>
> ... which I believe should be clarified in the spec before we make
> assumptions regarding these in the Linux driver. Otherwise, this is
> liable to vary in practice.
>
> Thanks,
> Mark.
>
> [1] https://trustedcomputinggroup.org/specifications-public-review/
> [2]
> https://trustedcomputinggroup.org/wp-content/uploads/TCG_ACPIGeneralSpecification-Family-1.2-and-2.0-Ver1.2-Rev8_public-revie....pdf
> [3]
> http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN0028B_SMC_Calling_Convention.pdf
next prev parent reply other threads:[~2017-04-14 4:58 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-11 11:36 ARM64 TPM start method patches Mark Rutland
2017-04-14 4:58 ` anjiandi [this message]
2017-04-14 6:37 ` Abdulhamid, Harb
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=9890ce2f139b4204d17c6a398681083f@codeaurora.org \
--to=anjiandi@codeaurora.org \
--cc=ard.biesheuvel@linaro.org \
--cc=harba@codeaurora.org \
--cc=jarkko.sakkinen@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=shankerd@codeaurora.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox